Chemical Synthesis, Characterization and Bioactivity Evaluation of Hydroxyapatite Prepared from Garden snail (Helix aspersa)

Abstract

An attempt is made to convert the calcium carbonate skeleton of widely available garden snail shell (Helix aspersa) to hydroxyapatite based bioceramics. The snail shell was found to decompose within 850oC to all the carbonate phases. The calcined snail shells were then treated with acids followed by different chemicals in ammoniacal media maintaining proper stoichemetry to produce fine Hydroxyapatite (HAP) as filter cake with Ca/P molar ratio of 1.67. The dried HAP powder was extremely pure with specific surface area of 15m2/g. The different characterization techniques were adopted both for calcined snail shell and HAP synthesized like X-ray Diffraction (XRD), Thermal Analysis (DTA/TGA) Figure 1, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The surface area and the particle size, of the HAP powder prepared by chemical precipitation route, were also determined by BET and Malvern particle size analyzer respectively. The synthesized powder was soaked in stimulated body fluid (SBF) medium for various periods of time in order to evaluate its bioactivity. The changes of the pH of SBF medium were measured. High bioactivity of prepared HAP powder due to the formation of apatite on its surface was observed.